shaddock vs Citrus maxima

shaddock and Citrus maxima both are nouns.

Word	Noun	Adjective	Verb	Adverb
shaddock	Yes	No	No	No
Citrus maxima	Yes	No	No	No

As nouns, shaddock and Citrus maxima are synonyms defined as:

shaddock and Citrus maxima: southeastern Asian tree producing large fruits resembling grapefruits

Other synonyms of shaddock include Citrus decumana, Citrus grandis, pomelo, pomelo tree, pummelo.

shaddock (noun)	Citrus maxima (noun)
large pear-shaped fruit similar to grapefruit but with coarse dry pulp	southeastern Asian tree producing large fruits resembling grapefruits
southeastern Asian tree producing large fruits resembling grapefruits